Collapsing tap



A. F. BREITENSTEIN COLLAPSING TAP Filed May 8. 1923 2 Sheets-Sheet l Q) 4A &pao a A. F. BREiTENS?ElN v COLLAPSING TAP Filed May 1923 2 Sheets-Sheet 2 Patented Sept. 30, 1924.

tic.

ALBERT F. BREITENSTEIN, NEW HAVEN, CONNECTICUT, ASSIG-NOR TO THE GEOMETRIO JIOOL (10., OF NEW HAVEN, CONNECTICUT, A CORPORATION.

GOLLAPSING TAP.

Application filed May 8,

To all whom it may concern:

Be it known that I, ALBERT F. BREITEN- STEIN, a citizen of the United States, resid ing at New Haven, in the county of New Haven and State of Connecticut, have invented a new and useful Improvement in Collapsing Taps; and I do hereby declare the following, when taken in connection with the accompanying drawings and the characters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this application, and represent, in s Fig. 1 a view in side elevation of a tap constructed in accordance with my invention and shown as collapsed.

Fig. 2 a view thereof, partly in plan and partly in section.

Fig. 3 a view thereof in front elevation.

Fig. 4 a view in central, longitudinal section, with the tap as expanded or set for cutting.

Fig. 5 a view in transverse section on the line 5-5 of Fig. 4. s

Fig. 6 a detached view of the operatinghandle of the tap.

My invention relates to an improvement in collapsing taps, the object being to pro duce a collapsing tap constructed with particular reference to simplicity, compactness, durability, efiiciency and low cost.

With these ends in View my invention consists in a collapsing tap having certain details of construction and combinations of parts as will be hereinafter described and particularly pointed out in the claims.

In carrying out my invention, as herein shown, I employ a pawl 10 arranged to swing in a plane parallel with the longitudinal axis of the tap in a longitudinal slot 11 formed in the periphery of a pawl-carrying ring 12 mounting a transversely-arranged pin 13, on which the pawl swings and which is encircled by a spring 14 arranged to exert a constant effort to swing the pawl outwardly into its locking position, in which it engages with the beveled forward edge of an annular flange 15 extending forward from a pawl-abutment ring 16 having internal threads adapting it to be mounted upon the threaded rear portion 17 of the tap-body 18, on which. the said ring is adjustable. The

1923. Serial No. 637,493.

said pawl 10 is swung inward into its unlocked position out of engagement with the flange 15 aforesaid by the engagement of its 26 formed integral with the forward end of a plunger 27 located in a bore 28 in the tap body, which is formed with a recess or cham ber 29 to receive the rear ends of the four ribs 26 when the plunger is retracted. The inner end of the tap-body is provided with a shank 30, by means of which it is mounted in the machine, whatever its character, in which the tap is used. This shank is formed with a concentric bore 31. and receives a plunger-screw 32, the threaded end of which enters a threaded bore 33 in the rear end of the plunger. A collapsing spring 34 encircling the plunger-screw impinges at its outer end against the head 35 thereof, while its inner end impinges against a washer 36 bearing against a shoulder 37 produced by making the bore 31 in the shank larger than the bore 28 in the tap-body 18, as clearly shown in Fig. 4.

For coupling the plunger 27 with the pawl-carrying ring 12, I employ a transversely arranged coupling bar 38, which passes through a diametric slot 39 in the plunger and through a clearance-slot 40 in the tap-body, its ends being entered into radial slots 41 in the said ring. This construction provides for the conjoint longitudinal movement of the plunger and pawlcarrying ring and prevents the rotation of the ring with respect to the body, the clearance-slot 40 being long enough to permit the plunger and ring to move forward and back, irrespective of the body, sufficiently to effect the projection and retraction of the chasers.

To effect the collapsing of the tap, I employ a tripping-plate 42 fastened by rivets 43 to the inwardly-turned ends of arms 44 adjustably secured by screw-bolts 45 to opposite points on the operating-sleeve 20, which, as aforesaid, has sliding movement upon the pawlcarrying ring 12. The adjustment of the plate 42 with respect to the object being tapped, predetermines the point at which the tap will be collapsed, and hence the depth of the thread. \Vhen the engagement between the plate 42 and the work takes place, the movement of the plate with the tap is arrested and hence the movement of the operating-sleeve 20, but not the other parts of the tap, so that the pawl 10, riding over the tripping-rib 19 of the said sleeve, will be swung inwardly and out of engagement with the flange 15 of the ring 17, thus unlocking the tap and permitting the collapsing-spring 34 to assert itself in collapsing the tap by retracting the plunger and hence retracting the chasers 22, which are set to fix the diameter of the thread to be cut by adjusting the ring 16, which is also used to compensate for the wear of the chasers. V

For re-setting the tap, I employ a handlever 46 hung on a pivot 47 in the operating sleeve 20, the inner end of the lever reaching through a clearance-slot 48 in the pawl carrying ring 12 and entering a socket-hole 49 in the body 18. For excluding dirt and foreign matter from the tap, the handle 46 is formed with a spherically-contoured, dirtexcluding closure 50 centered about the said pivot 47 and working in a cylindrical passage 51 in the sleeve 20 in such a manner as to effectually exclude dirt and foreign matter from the tap.

To reset the tap, the lever 46 is grasped and thrown forward from the position in which it is shown in Fig. 1, into the position in which it is shown in Fig. 4, whereby the operating-sleeve and pawlcarrying ring are slid forward, and as the plunger is connected with the pawlcarrying ring by means of the coupling-bar 38, the plunger is correspondingly moved forward, with the effect of projecting the chasers lnto thelr cutting-positions and compressing the collapsmg-sprmg.

This forward movement of the pawl-carrying ring is continued until the pawl carried by it has been so far moved forward that its spring 14 is permitted to act to swing it outward into position to engage with the beveled edge of the flange 15 of the pawlabutment ring 16. Therefore, while the tap is automatically collapsed by the work, the tap is manually re-set by its handle 46.

I do not, in this application, broadly claim the use, in a collapsible tap, of a pawl arranged to swing in a plane parallel with the longitudinal axis of the tap, that broad subject-matter having been claimed in my co-pending application Serial Number 637,492, filed; in even date herewith.

I claim:

1. In a collapsing tap, the combination with the body, Chasers, plunger and collaps ing-spring thereof, of a pawl-carrying ring having sliding movement upon the said body and coupled with the plunger for movement therewith, an operating-sleeve having sliding movement upon the pawlcarrying ring, a pawl mounted in the pawlcarrying ring in position to be tripped the sliding movement of the operating sleeve, means co-act-ing with the said pawl to hold the chasers in their cutting positions, and a, hand-lever mounted in the operating-sleeve for moving the same and the pawl-carrying ring for resetting the tap.

2. In a collapsing tap, the combination with the body, chasers, plunger and collapsing-spring thereof, of a pawl-carrying ring having sliding movement on the said body and coupled with the plunger vfor movement therewith, an operating-sleeve having sliding movement upon the pawlcarrying ring, a pawlmounted in the pawlcarrying ring in position to be tripped by the sliding movement of the operating sleeve and swinging in a plane parallelwith the longitudinal axis of the said body, and anadjustable pawl-abutment ring mounted upon the tap-body and engaged by the pawl for holding the said chasers in their cut- 10 ting positions.

3. In a collapsing tap, the combination with the body, chasers, plunger and collapsing-spring thereof, of a pawl-carrying ring having sliding movement upon. the c said body and coupled with the plunger for movement therewith, an operatingsleeve having sliding movement upon the pawlcarrying ring, an adjustable pawl-abutment ring mounted upon the body, a pawl mounted in the pawl-carrying ring to swing in a plane parallel. with the longitudinal axis of the. tap and co-acting with the said pawl-abutment ring for holding the said chasers in their cutting-positions, an adjustable tripping-plate carried by the opcrating-sleeve and interposed between the same and the forward ends of the chasers, and a hand-operated lever mounted in the operating-sleeve and engaging with the said body for sliding the said sleeve and the pawl-carrying ring with respect thereto.

4. In a collapsing tap, the combination with the body, chasers, plunger and collapsing-spring thereof of a ring having sliding movement upon the said body and coupled with the said plunger for movement therewith, a sleeve. having sliding movement upon the said ring, a detent carried by the said ring and tripped by the sliding movement of the sleeve thereupon,

means co-acting with the said detent to hold specification in the presence of two subscribthe Chasers in their projected positions ing witnesses.

against the power of the said sprin and a T T hand-1ever mounted in the said sleeve for ALBERT BREITELSTEIA' 5 moving the same and the said ring and Vitnesses:

plunger for resetting the tap. GEORGE L. DRAFFAN,

In testimony whereof, I have signed this FREDERICK O. UIHLEIN. 

